Cerebrospinal fluid levels of insulin in patients with Alzheimer's disease.

OBJECTIVES: Some previous reports suggested a potential role of insulin in memory and in the pathophysiology of Alzheimer's disease (AD). We assessed the cerebrospinal fluid (CSF) levels of insulin in patients with AD and in age and sex-matched controls trying to elucidate whether this value could be related with the risk or severity of AD. PATIENTS AND METHODS: We measured the CSF insulin levels in 27 patients with AD and 16 matched controls using a RadioImmunoanalysis method. RESULTS: CSF insulin levels did not differ significantly between AD-patient and control groups. These values were not correlated with age, age at onset, duration of the disease, and scores of the MiniMental State Examination in the AD group. CONCLUSION: These results suggest that CSF insulin concentrations are not related with the risk or severity of AD.